Zuckerberg needs to testify before Congress in an open hearing about Facebook’s business model and the design priorities for its algorithms, and defend his view that Facebook is not responsible for what third parties do on its platform.

Facebook did not set out to increase political polarization and empower bad actors to undermine democracy, but this outcome was inevitable. It was the result of countless Facebook decisions, all made in pursuit of greater profits. In order to maximize its share of human attention, Facebook employed techniques designed to create an addiction to its platform. It deploys digital trackers to monitor and monetize the digital lives of its users. As a result, Facebook has emerged as one of the most profitable companies in our economy.

Facebook has created bubbles around users that contrary ideas — and even facts — cannot penetrate, empowering groups of like-minded people to share emotionally charged ideas on a platform that is vulnerable to exploitation by bad actors.

The harm goes way beyond the Russians and the election, and it is ongoing. Significantly, Facebook takes the position that its only policing obligation is to support community standards on issues such as displays of nudity. As a result, it was not even looking for, much less working to prevent, interference in our elections. In retrospect, Facebook’s architecture and the lack of surveillance invited malicious interference in the 2016 election. For a trivial sum, the Russians were able to wreak havoc. A congressional committee is investigating to what extent they exploited other platforms — 4chan, Reddit, Twitter and Google — but so far it appears Facebook was the one that did the most damage.

The issues with Facebook’s business model have not gone unnoticed. For several years, the advocacy group Common Sense Media has been decrying the public health threat to children from addiction to social media. Two years ago, former Google design ethicist Tristan Harris launched Time Well Spent to help people fight social media addiction.

I noticed a disturbing pattern of behavior on Facebook in early 2016 surrounding Black Lives Matter, the Democratic primaries and Brexit. I reached out to Mark Zuckerberg and Sheryl Sandberg before the election to call their attention to what I was seeing. They dismissed my concerns, just as they would dismiss those of President Obama nearly a month later. Zuckerberg called concerns about Facebook’s role in the election “crazy.”

With the benefit of hindsight, Zuckerberg’s several blog posts on the matter could have been attempts to distract us. Zuckerberg needs to come clean. To this point, much of what we know about Russian exploitation of Facebook has come from third parties rather than Facebook itself. That has to change.

Facebook depends on trust. Consumers know Facebook spies on them, but they assumed it was harmless. The recent revelations have harmed the company’s brand and Zuckerberg’s reputation. If my hypothesis is correct and more evidence of Russian political interference on Facebook comes to light, trust in Facebook will erode further. It was one thing to trust an American company with our personal information, but quite another to trust a hostile foreign power. The company’s best hope for salvaging its reputation is to come clean.

It cannot be easy for Facebook employees to accept that their platform has been accused of undermining democracy in the United States, United Kingdom, France and Germany, but that is where we are. Facebook must accept responsibility for the harm caused by the choices it made. When Zuckerberg and team do that, and take actions to prevent further damage, it will be time to forgive them.

Roger McNamee, an early investor in Facebook and Google, is the managing director and co-founder of Elevation Partners.